Ok so I've looked on the internet and never really seen a sound answer for a N/A build for a 99-04 2V Build to get to 400RWHP. I would like to think we'd all like to get our GT's to that power beings that 230RWHP isn't really anything to brag about nowadays. as well that mostly anything GM Made in these years ousted us by at least 75HP. so what would the average guy need no limit of fund. keep the block as stock as possible minus top end Exhaust, bolt ons. etc. I would think on a stock block you would need a set of TFS heads with maybe a more aggressive porting, a set or very aggressive cams. a set of LT's O/R X Or H, and a Catback of your choice. a TF Heat intake, Throttle body and space and cai, a set of Underdrive Pullies (Steeda). what do you guys think. and yes we all know you can just spray or put a blower on it and get the same power and it be cheaper. some of us want to know more.

 

NO STROKER BUILD BTW!

 

To get 400rwhp, a 4v or 3v top end is needed. A 2v with trick flow heads and decent cams will only be in the 350 rwhp range. I don't think I have heard of a n/a 2v going 400hp plus. Even with a 4v or 3v top end, aggressive cams will be needed. Our poor little 281 cubic inches don't make power easy without a power adder.

 

that's why I was saying with a even more aggressive port to the TFS heads and maybe some turbo grind cams and full exhaust id think would just about get us there maybe 385. maybe with upgraded fuel system and maybe some race gas would get us well into the 400s. CMON GUYS I KNOW WE CAN FIGURE THIS OUT! haha

 

I don't know what it will take to hit 400 n/a. I assume, 5.4l big bore to a 5.8L with ported 03-04 cobra heads, forged internals, custom intake and rev the **** out of it. Or and I know this gets thrown out there a lot, just supercharge your 2v with blower cams and a good intercooler :3 so much cheaper.

 

Pretty close, I doubt that you would need the big bore kit though. I have heard of H/C/I 5.4L DOHC engines hitting 400RWP with high compression.

 

Yeah but 5.8l big bore sounds bad ***. I forgot about the high compression part. It can be done, but how much do you want to spend to only get to 400.

 

As stated before though No stroker/ Big bore stock 4.6 block with 2 vakve heads. there would has to be a way. we all know you can add displacement and get more power we all know you can spray your way to 400 and we all know you can blow your way to 400. Im talking Serious sleeper 4.6 nothing else. anything up top could be changed. I would highly imagine 400 can be reach with 2valve heads. ported 4v heads is all over the internet and can be reach 400rwhp. I think personally I have imagined and smart build list. My opinion I always wanted the engine to look as stock as possible.

 

bro its not going to happen. 380hp at the wheels is about 400hp at the motor.

 

Why 400whp? Why stock internals? What's your goal exactly?

I think you're on the right track to get max power, but it won't be 400whp. However, if it's bragging rights you're after, I think you'll get them with being able to say you make X amount of HP with only a 4.6L SOHC NA. If you build the top end as described, all bolt-ons, long tubes, x-pipe, and a really solid A/F map. I'm guessing 320-340whp.